<title>Gyrator</title>
<link rel="SHORTCUT ICON" href="favicon.ico">
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<table><tr><td>
<applet code=Circuit.class archive=circuit.jar width=640 height=450>
Sorry, you need a Java-enabled browser to see the simulation.
<param name=pause value=20>
<param name=startCircuit value="gyrator.txt">
<param name=startLabel   value="Gyrator">
<param name=useFrame     value="false">
</applet>
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<p>
The circuit on top uses a <a href="http://en.wikipedia.org/wiki/Gyrator">gyrator</a> to simulate
an inductor.  Inductors can be bulky, heavy, and expensive,
so it is often valuable to replace them with cheaper components.  The circuit being simulated
is on the bottom.
<p>
The capacitor passes high frequencies (and sudden changes), causing the + input of the op-amp to be closer to the
input signal.  (Because of the large (20k) resistor, there isn't much current through the
capacitor, though.)  The op-amp keeps the &ndash; input at the same level as +, causing
less current to pass through the 1k resistor, because the voltage is nearly the same
as the input.  The circuit blocks high frequencies, like an inductor.
<p>
The capacitor blocks low frequencies (and steady voltages), causing the + input of the op-amp to be closer to ground.
The op-amp keeps the &ndash; input at the same level as +, causing
more current to pass through the 1k resistor to ground; it passes low frequencies, like an
inductor.

<p>
Next: <a href="e-capmult.html">Capacitance Multiplier</a><br>
Previous: <a href="e-nic-r.html">Negative Impedance Converter</a><br>
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<br>Generated Tue Dec  7 2010
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